Current Electricity Class 12 MCQs Questions with Answers

1. Two conductors of equal length and radii the ratio of 2 : 3 are; connected in parallel the source of electricity. The ratio of the velocity of electrons in the conductor be :

2. Drift velocity of electrons is due to

3. The example of a non-ohmic resistance is:

4. When no current is passed through a conductor,

5. To draw a maximum current from a combination of cells, how should the cells be grouped?

6. A charge is moving across a junction, then

7. Constantan wire is used for making standard resistance, because it has

8. A current passes through a resistor. If K1 and K2 represent the average kinetic energy of the conduction electrons and the metal ions respectively then

9. Thermo electricity was discovered by:

10. The heat sensitive device whose resistivity changes very rapidly with change of temperature is called a :

11. Two cells of emf’s approximately 5 V and 10 V are to be accurately compared using a potentiometer of length 400 cm.

12. In parallel combination of n cells, we obtain

13. A galvanometer acting as a volt meter will have with its coil.

14. In India electricity is supplied fordomestic use at 220 V. It is supplied at 110 V in U.S.A. If the resistance of a 60 W bulb use in India is R. the resistance of a 60 W bulb for use in USA will be:

15. Combine three resistors 5 Q, 4.5 Q and 3 Q in such a way that the total resistance of this combination is maximum

16.  
In the series combination of two or more than two resistances

17. The current which is assumed to be flowing in a circuit from positive terminal to negative, is called

18. Siemen is the unit of:

19. Nichrome or Manganin is widely used in wire bound standard resistors because of their

20. When a metal conductor connected to left gap of a meter bridge is heated, the balancing point